YOU have seen, in the foregoing chapter, what means and methods you are to use, to raise and improve your devotion; how early you are to begin your prayers, and what is to be the subject of your first devotions in the morning.
There is one thing still remaining, that you must be required to observe, not only as fit and proper to be done, but as such as cannot be neglected without great prejudice to your devotions: and that is to begin all your prayers with a psalm.
This is so right, is so beneficial to devotion, has so much effect upon our hearts, that it may be insisted upon as a common rule for all persons.
I do not mean, that you should read over a psalm, but that you should chant or sing one of those psalms, which we commonly call the reading psalms. For singing is as much the proper use of a psalm as devout supplication is the proper use of a form of prayer; and a psalm only read is very much like a prayer that is only looked over.
Now the method of chanting a psalm, such as is used in the colleges, in the universities, and in some churches, is such as all persons are capable of. The change of the voice in thus chanting of a psalm is so small and natural, that everybody is able to do it, and yet sufficient to raise and keep up the gladness of our hearts.
You are, therefore, to consider this chanting of a psalm as a necessary beginning of your devotions, as something that is to awaken all that is good and holy within you, that is to call your spirits to their proper duty, to set you in your best posture towards heaven, and tune all the powers of your soul to worship and adoration.
For there is nothing that so clears a way for your prayers, nothing that so disperses dulness of heart, nothing that so purifies the soul from poor and little passions, nothing that so opens heaven, or carries your heart so near it, as these songs of praise.
They create a sense and delight in God, they awaken holy desires, they teach you how to ask, and they prevail with God to give. They kindle a holy flame, they turn your heart into an altar, your prayers into incense, and carry them as a sweet-smelling savour to the throne of grace.
The difference between singing and reading a psalm will easily be understood, if you consider the difference between reading and singing a common song that you like. Whilst you only read it, you only like it, and that is all; but as soon as you sing it, then you enjoy it, you feel the delight of it; it has got hold of you, your passions keep pace with it, and you feel the same spirit within you that seems to be in the words.
If you were to tell a person that has such a song, that he need not sing it, that it was sufficient to peruse it, he would wonder what you meant; and would think you as absurd as if you were to tell him that he should only look at his food, to see whether it was good, but need not eat it: for a song of praise not sung, is very like any other good thing not made use of.
-- from Chapter 15 of A Serious Call to a Devout and Holy Life by William Law
Psalms are songs. They may be strange to our western sense of music, especially if one has a miserable voice and a tin ear as I do. Still, even I can chant. Imagine Lou Reed doing Psalm 23 instead of "Walk on the Wild Side". I may not be able to carry a tune, but I can get in tune, which is the purpose.